Change-speed gearing for lathe headstocks



SepLZG, 1950 H.YJ. SIEKMANN ETAL. 2,523,397

I cmmcs SPEED GEARING FOR LATi-IE HEADSTOCKS Filed Sept. 10, 1948 5 Sheets-Shae; 1 j

IN V EN TORS. HAROLD J. .SlE/(MANN AND BY 65 01965 J. KASSELMANN ATTORNEY Sept. 26, 1950 H. J. SIEKMANN E TAL 2,523,397

cmmcs SPEED GEARING FOR LATHE HEADSTOCKS Filed Sept. 10, 1948 5 Sheets-Sheet 2 INVEN TORS. 3 Y HAROLD J. SIEKMA NM Mm GEORGE J. KASSELMAMV .H. J. SIEKMANN EI'AL- 2,523,397

CHANGE SPEED GEARING FOR LATHE HEADSTOCKS Filed Sept. 10., .1948

Sept. 25, 1950 5 Sheets-Sheet 3 w /////W/// S 62 IN VEN TORS.

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A 7' TORNE Y P 6, 1950 H. J. SIEKMANN QETAL 2,523,397.

CHANGE SPEED GEARING FOR LATHE HEADSTOCKS Filed Sept. 10, 1948 i 5 Sheets-sheaf 4 INVENTORS. HA now .1. S/EKMAN/V m saunas .1. x4 SSELMA um "ham 3. M

A TTORNE Y p 1950 4H. J. SIEKMANN arm. 2,523,397

CHANGE SPEED GEARING FOR LATHE HEADSTOCKS Filed Sept. 10, 1948 5 Sheets-Sheet 5 5 i (8 0 -1 m INVENTORS.

."2 HAROLD .1. 515mm A!!! GEORGE .1; mssnmw BQQQM ATTUIM'E'Y Patented Sept. 26, 1950 UNITED STATES- PATENT OFFICE CHANGE- SPEED GEARING FOR LATHE HEADSTOCKS Application September 10, 1948, Serial No. 48,738

Claims.

This invention pertains to improvements in lathe headstock transmissions and is particularly directed to improvements in the arrangement of the-gear train and driving transmission mechanism of the headstock.

In lathe headstock transmissions for metal turning machines, it is most important to provide a power transmission for the work spindle which'has a wide range of speeds so as to adapt the machine to all of the various forms of work it may be put to. Oneof the objects of this invention is to provide an improved and simplified transmission gearing mechanism which is capable of providing 16 different spindle speeds for the headstock transmission.

Another object of this invention is to provide an improved gear train arrangement and shifting mechanism therefor for a lathe headstock capable of providing a wide variety of different spindle speeds.

Still another object of this invention is to provide a lathe headstock transmission with a high and low range of speeds, the high range of which is accomplished through a direct belt-drive to the work spindle.

Further features and advantages of this invention will appear from a detailed description of the drawings in which:

Figure l is a diagrammatic sectional view of a lathe headstock transmission incorporating the features of this invention.

Figure 2 is a fragmentary diagrammatic view of the control lever and gear shifting mechanism of the headstock transmission of Figure 1.

Figure 3 is a fragmentary section on the line 85 3-3 of Figure 2.

Figure 4 is a fragmentary front elevation of the lathe headstock transmission showing further details of the gear shifting mechanism.

Figure 5 is an end view of the belt drive transmission of the headstock indicated by the line 55 in Figure 1.

Figure 6 is a sectional view through the belt drive transmission indicated by the line 66 in Figure 5.

Figure '7 is a view similar to Figure 6 but showing the belts in fully stretched adjusted position.

As an exemplary embodiment of this invention there is shown, Figure 1, a headstock housing III, which has an input shaft ll suitably journalled on bearings I2 and I3 supported on the headstock housing ill. The input shaft ll carries the main driving pulley l4 which is driven by suitable belted means from a main drive motor not shown. Journalled on the input shaft II are the gears i5 and I6 each of which may be respectively connected to or disconnected from the driving power from the input shaft I I by clutches I! and I8 actuated by the usual shifting spool l9. On

5 a first intermediate shaft 20 journalled on suit-- able bearings 2| and 22 in the headstock housing I0 is the gear 23 which is in constant mesh with and driven by the gear IS on the input shaft I l. A second gear 24 formed on the first intermediate shaft is driven from the gear IS on the input shaft ll through an intermediate -.idler gear 25 journalled on a shaft 26 fixed in the headstock housing In so that by engaging one or the other of the clutches l1 and t8 the 14 first intermediate shaft 20 may be caused to a the main drive motor actuating the input pulley l4.

A second intermediate shaft 21 is journalled on suitable bearings 28, 23, and 30 in the headstock housing l0 and has journalled on it a 85 gear 3! which is continuously in driving engage- 30 34 adapted to engage a mating clutch portion 35 of the gear 3! when the gear 33 is shifted to its extreme left position, Figure 1. In this way the gear 3| drives through the triple gear 33, the shaft 21.

A gear 36 formed on the triple gear may be shifted into engagement with a gear 31 formed on the shaft 20. While the gear 38 of the triple gear may engage the gear 33 formed on the shaft 21% and finally the gear 33 may be shifted to its 40 extreme right position, Figure l, to engage its gear an with the gear 24 of the first intermediate shaft 20. Thus by shifting the triple gear 33 to the 4 positions above indicated four different speed changes may be applied from the shaft 23 to the second intermediate shaft 21.

A back gear shaft 4| is journalled on suitable bearings 42 and 43 in the headstock housing In and has a spline portion upon which is slidingly mounted the shiftable triple back gear 44. The

triple gear 44 may be shifted to its extreme right position, Figure 1, so that its gear 45 will be in engagement with a gear 46 formed on the second intermediate shaft'21, and its gear 41 will be in engagement with the large face gear 48 fixed to 56 the work spindle 49 of the lathe, the work spindle being journalled on suitable bearings 58. II, and

82 in the headstock housing |8. The gear 44 may be shifted to a second position to the left, Figure 1, with the gear 48 still in engagement with the gear 48, but in which case the gear 48 is also shifted into position with a gear 58 on the work spindle 48. A third position still further to the left of the gear 44 brings its gear 54 into engagement with a gear 55 formed on the second intermediate shaft 21 while the gear 45 remains in engagement with the gear 58 on the work spindie 48.

A final high speed driving position is provided by shifting the triple gear 44 to extreme left osition, Figure l, in which case the drive is through the gear 55 to the gear 54 and then from the gear 45 to a gear 58 fixed on the belt drive shaft 81 journalled on suitable bearings 58 and 58 in the headstock housing II. On the outer end of the belt drive shaft 51 is a V-belt pulley or sheeve 88 which drives through suitable belts a sheeve 8| fixed on the work spindle 48 so that in this speed the final high speed drive to the work spindle 48 is accomplished through direct belted driving means to the pulley 8| on this spindle.

It is also to be noted that in connection with 1 the change from the three back gear ranges of speeds to the belt drive high speed that the feed drive is likewise slowed down in the high speed belt drive position. Normally in the three slower geared back geared drives to the spindle the feed gear 82 keyed in driving sliding relationship at 53 on the spindle 48 has a gear 84 which remains in driving engagement with a gear 85 on the feed shaft 88 journalled in suitable bearings 81 and 88 in the headstock housing l8. When the triple back gear 44 is shifted to the belt drive position with its gear 45 in driving engagement with the 1 gear 58, its gear 54 also drives through a gear 88 journalled on a stud 18 in the headstock housing II, a gear 1| fixed on the feed drive shaft 88, while the gear 84 is shifted to the extreme right position out of engagement with the gear 85.

Thus, in this latter position the feed drive power I comes from the second intermediate shaft through the triple back gear 44 and the work spindle 48 is eliminated from the feed drive transmission. This gives a reduced feed and also gives a positive drive around the belt drive at the high speeds to the feed drive train. Thus fine feeds at high belt speeds are obtained while the transmission automatically reverts to the normal direct spindle drive of the feed transmission in the three lower ranges of back gear speeds. A suitable power take-off gear 12 fixed to the shaft 88 and the gear 85 drives the feed mechanism indicated generally at 13 for actuation of the cutting tool by apparatus of a conventional and well known character.

Thus, by the appropriate sequential shifting of only two triple gears 83 and 44 sixteen driving speeds including a belt drive in the higher range is provided for the work spindle 48. By shifting the feed selector gear 62 in proper time sequence with the shifting of the aforementioned triple gears 33 and 44 the feed drive is automatically reduced while maintained P sitive in its driving action to the feed mechanism when the high speed belt-drive is cut in. It should be further noted that the simplicity of parts involved by this unique arrangement of a headstock transmission of the rocking sleeve 11 journalled in a suitable bearing 18 in the headstock housing l8 and con-- fined against axial movement therein by abutment against the face 18 of the headstock l8 and by the lock nut 88 threaded to the inner end of the sleeve 11. Inside of the sleeve 11 is an axially movable rock shaft 8| which is pivotally connected at 82 to the lever 14 and extends inwardly of the headstock and is supported at its rear end in a suitable journal bearing 88 in the headstock Ill. The shaft 8| may be rocked by the lever 14 to a series of positions 14a, 14b, 14c and 14d, Figure 4, by the rocking ofthe sleeve 11 in the bearing 18. The rock shaft 8| may be moved axially in and out to four positions by actuation of the lever-14 to the positions 14c, 141, 14g and 14h, as seen. in Figure 3. A suitable ball detent 84 locates the lever 14 in' any of the four positions 14a, to 14d inclusive, while a balldetent 85 carried inthe sleeve 11 engages detent notches 88 of the rock shaft 8| to locate the control lever 14 in any of the four positions 14a to 14h inclusive.

Fixed to the rock shaft'is an indicating pointer 81 by a suitable screw 88 so that the pointer 81 partakes of the rocking motion of the sleeve member 1| and also the in and out motion of the rock shaft 8|.- The pointer 81 is related to a suitable index plate 88 fixed on the surface |8a of the headstock housing |8 to show the selective speed obtained by positioning the lever 14. The in and out motion of the lever 14 whic axially shifts the rock shaft 8| is conveyed through a spool 88 fixed to the inner end of the rock shaft 8| to actuate the lever arm 8| of the bell crank shifter lever 82 journalled on a suitable shaft 83 fixed in the headstock 18. A second v arm 84 formed integral with the bell crank lever 82 reaches out with a shoe engaging in the. annular groove 88 of the triple gear 38, so that axial shifting of the rock shaft 8| shifts the gear 38 to its four shiftable positions.

The rocking motion of the shaft 8| affected by moving the levers to positions 14a to 14d inclusive is conveyed through a lever 81 splined in sliding driving engagement with the spline portion 8|a of the shaft 8|, the member 81 also having an extended portion 88 journalled in a suitable bearing support 88 of the head stock housing l8 and held against axial movement therein by a suitable locking ring |88 so that the member 81 may rock in the journal 88 but is confined against axial movement relative to the headstock. The lever 81 has a link |8| pivotally connected to a pin I82, the other end of the link |8| being pivotally connected through a pin |82a to a shifter lever I83 pivotally mounted on a suitable stud |84 fixed to the headstock housing, |8. The lever I83 has an arm I85 terminating in a shoe |88 operating in the annular groove I81 of the affecting the back gear or belt-drive of the lathe headstock. An arm |88 of the lever |88 is connected through a pin |88 to a link 8 which in turn is connected through a, pin III to a lever ||2 pivotally mounted against axial movement on an extension 3 of the member 88 and has a downwardly extending lever I I4 terminating in a shoe 5 operating in the annular groove 8 of the shiftable gear 82 so that as the lever 14 is rocked to any of the positions 14a to 14d the feed gear speed change from high belt speed to back gear drive will be automatically affected. Thus the single lever I4 controls all of the sixteen speed changes and the feed rate change for the lathe headstock transmission.

Installation, removal and adjustment of the driving belts I20 between the pulley and BI is accomplished by unique arrangement shown best in Figures 5, '6, and 7. On the drive shaft 01 is fixed a pulley hub I2I by a suitable lock nut I22. The outer periphery of the hub I2I has a continuous thread I23 extending along its entire diameter. An axially extending keyway I24 adapted to receive a key I which is held in place by a suitable screw I20 threaded into the huh I 2 I at I21. 0n the outer threaded periphery of the hub I2I is a series of sheeve forming rings I 23, I20 and I30, all of which may be rotated and moved along axially in any desired position on the periphery of the hub I2I. Slots I 3| are formed at six places in the threaded bores oi the members I20, I20, and I30 so that they may be rotated to bring a series of slots in alignmentas at I3Ia, Figure 5, and the key I25 inserted therethrough as shown in Figure 6 to lock all of the collars I20, I 20 and I in desired axial driving position on the hub I2I.

On the driven spindle 49 is fixed a pulley hub I32 of the pulley BI which has a series of three feed belt grooves I33 formed therein. A second pulley member I34 is axially slidable in driving engagement through a key I35 on the diameter portion I36 of the pulley hub I32. Abutment screws I31 and draw in screws I38 serve to accurately axially position the pulley member WI and to lock it into any adjusted axial position.

Thus, by removing the various rings I 28, I29 and I30 from the pulley hub Hi the various V-beits I20 may be readily installed on or removed from the shafts 49 and 51 without disturbing their center distances on their journal bearings. When the belts are new and just have been placed on the pulleys as shown best in Figure 6, the two pulley assemblies assume the relationship shown. Belt A is positioned in perfect alignment with both pulleys along the line I39, while belts B and C are slightly divergent with regard to the lines I40 and I at the pulley 60. The remaining belts D and E are also slightly divergent along the lines I42 and I43 toward the pulley 60. The pulley I34 is moved to maintain this general relationship of the belts D and E with regard to the V-grooves I44 and the grooves formed in the pulley 00. After the belts wear and it is desired to take up tension in them, the two sheeve forming collars F and G are moved toward each other as shown in Figure '7, still maintaining the exact alignment of the belt A along the line I39 for both pulleys 60 and GI. The outer collar I28 marked H is moved inwardly to the left as shown in Figure 7 while the collar I is moved toward the right toward the collar F which results in a slightly convergent condition of the belt I20 toward the pulley 00. The sheeve forming ring. J

is moved up against the ring I while the final ring K is moved up toward the ring J as seen in Figure 7. At the same time the pulley member I34 is moved to the right, Figure 7, to maintain a condition of slight convergence of the belts D and E toward the pulley 60. Thus a wide range of selection of; belt tensions may be obtained while at the same time avoiding the necessity of disturbing the shaft center distances or dismounting them in any way from the journal bearings and at the same time maintaining sub-,

stantial correct alignment of the belts in approaching and receding from the V-grooves in the pulleys.

While the apparatus herein disclosed and described constitutes a preferred form of the invention, it is to be understood that the apparatus is capable of mechanical alteration without departing from the spirit of the invention and that such mechanical arrangements and commercial adaptations as fall within the scope of the apfiendant claims are intended to be included here- Having thus fully set forth and described this invention, what is claimed as new and desired to be secured by United States Letters Patent is:

1. In a lathe headstock transmission, a work spindle, a large diameter face gear on said work spindle, a second smaller gear on said work spindle, and a belt drive transmission for actuating said'work spindle, an input shaft, a first inter mediate shaft, a forward and reverse driving connection from said input shaft to said first intermediate shaft, a second intermediate shaft, a gear journaled on said second intermediate shaft and constantly driven from a gear on said first intermediate shaft, a shiftable triple gear mounting in sliding driving connection on said second intermediate shaft selectively engageable with a series of three mating gears on said first intermediate shaft, a back gear shaft, a back gear triple gear axially shiftably mounted on said back gear shaft having a small gear, an intermediate gear, and a large gear formed thereon, a small diameter wide faced gear on said second intermediate shaft, a larger diameter wide faced gear formed on said second intermediate shaft, said back gear triple gear being shiftable to a plurality of positions wherein the large gear of said back gear triple gear at one time engages the small wide face gear on said second intermediate shaft while the small gear of said triple gear engages said large diameter face gear on said work spindle, in a second shaft position said large gear remains in engagement with the small wide faced gear of the second intermediate shaft while engaging said second smaller gear on the work spindle, and shiftable to third position where the intermediate gear of said back gear triple gear is driven from the larger diameter gear of the second intermediate shaft while the large gear of the back gear triple gear maintains driving engagement with the smaller gear on the work spindle, and shiftable to a fourth position wherein the back gear triple gear continues to be driven from the larger diameter gear of the second intermediate shaft while its large diameter gear drives a belt drive transmission for actuating the work spindle.

2. In a lathe headstock transmission, a work spindle, a large diameter face gear on said work spindle, a second smaller gear on said work spindie, a belt drive transmission for actuating said work spindle, feed mechanism, and a regulating gear operable to drive said feed mechanism, an input shaft, a first intermediate shaft, a forward and reverse driving connection from said input shaft to said first intermediate shaft, a second intermediate shaft, a gear journalled on said second intermediate shaft and constantly driven from a gear on said first intermediate shaft. a shiftable triple gear mounting in sliding driving connection on said second intermediate shaft selectively engageable with a series of three mating gears on 7 said first intermediate shaft, a back gear shaft. a back gear triple gear axially shiftably mounted on said back gear shaft having a small gear.

an intermediate gear, and a large gear formed thereon, a small diameter wide faced gear on said second intermediate shaft, 9. larger diameter wide faced gear formed on said second intermediate shaft, said back gear triple gear being shiftable to a plurality of positions wherein the large gear of said back gear triple gear at one time engages the small wide face gear on said second intermediate shaft while the small gear of said triple gear engages said large diameter face gear onsald work spindle, in a second shaft position said large gear remains in engagement with the small wide faced gear of the second intermediate shaft while engaging said second smaller gear on the work spindle, and shiftable to third position where the intermediate gear of said back gear triple gear is driven from the larger diameter gear of the second intermediate shaft while the large gear of the back gear triple gear maintains driving engagement with the smaller gear on the work spindle, and shiftable to a. fourth position wherein the back gear triple gear continues to be driven from the larger diameter gear of the second intermediate shaft while its large diameter gear drives said belt drive transmission for actuating the work spindle and said regulating gear operable to drive said feed mechanism directly from the work spindle in the first three aforementioned shift positions for the back gear triple gear and to drive the said mechanism in the fourth belt-drive position directly from the second intermediate shaft.

3. In a lathe headstock transmission having, a work spindle, and feed mechanism actuated from said transmission, on input shaft, a first intermediate shaft, :3, forward and reverse driving connection between said input and first intermediate shafts, a second intermediate shaft. gearing means affecting a plurality of speed changes between said first intermediate shaft and said second intermediate shaft, and back gearing and belt driving connections between said second intermediate shaft and said work spindle. a feed rate change drive to said feed mechanism of the lathe, a back gear shaft, a back gear triple gear having small, intermediate and large gears formed thereon axially shiftable on said back gear shaft to a series of four positions, a small and a large wide faced gear on the second intermediate shaft, a small and a large gear on said work spindle, and a belt drive gear selectively engageable by shifting of said back gear triple gear, a belt drive shaft carrying said belt drive gear, feed change gearing in said feed mechanism interconnectable with said spindle or with said second intermediate shaft by shifting of said back gear triple gear, and a belt driving connection from said belt drive shaft to said work spindle.

4. In a lathe headstock transmission having, a work spindle, an input shaft, 9. first intermediate shaft means for driving said first intermediate shaft from said input shaft, a second intermediate shaft, change speed gearing means between said first and said second intermediate -8 shafts for affecting a plurality of different speeds in said second intermediate shaft, small and large output gears on said second intermediate shaft, small and large input gears on the work spindle of said lathe headstock transmission, a belt drive for said spindle including a belt drive shaft, an input gear on said belt drive shaft, and a pulley on said belt drive shaft connected through sultahle belt means to a belt pulley on the work spindle, and aback gear shaft having a shiftable back gear triple gear mounted thereon adapted to selectively engage the output gears on the intermediate shaft, the input gears on the work spindle and the gear on the belt drive shaft to provide a series of three back gear drive connections and a belt drive connection to the work spindle.

5. In a lathe headstock transmission having, 'a work spindle, an input shaft, a first intermediate shaft means for driving said first intermediate shaft from said input shaft, a second intermediate shaft, change speed gearing means between. said first and said second intermediate shafts for affecting a plurality of different speeds in said second intermediate shaft, small and large output gears on said second intermediate shaft, small and large input gears on the work spindle of said lathe headstock transmission, a

belt drive for said spindle including a belt drive shaft, an input gear on said belt drive shaft, and a pulley on said belt drive shaft connected through suitable belt means to a .belt pulley on the work spindle, and a back gear shaft having a shiftable back gear triple gear mounted thereon adapted to selectively engage the output gears on the intermediate shaft, the input gears on the work spindle and the gear on the belt drive shaft to provide a series of three back gear drive connections and a belt drive connection to the work spindle. and a feed drive mechanism for the lathe having gearing means directly connecting driving power from said spindle to the feed mechanism when the shiftable back gear triple gear is in any of the three back gear drive positions and disengageable when the shiftable back gear triple gear is in belt drive position of engagement with the gear on the belt drive shaft, and means when said last mentioned drive is in effect to drive the feed mechanism of said lathe from said second intermediate shaft.

HAROLD J. SIEKMANN. GEORGE J. KASSELMANN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 00 1,881,028 Meyer Oct. 4, 1932 1,947,862 Lucas Feb. 20, 1934 2,197,893 LeBlond et al Apr. 23, 1940 2,239,443 Groene et al Apr. 22, 1941 2,247,491 Groene July 1, 1941 2,253,921 Van Sant Aug. 26, 1941 2,338,121 LeBlond Jan. 4, 1944 

